1. Field of Invention
The present invention relates to an electric vehicle, and more particularly to an electric vehicle with electric-free driving system, which can be selectively impelled by electrical power or by manually.
2. Description of Related Arts
A conventional electric vehicle comprises a supporting frame, a wheel assembly comprising at least two wheels spacedly and rotatably mounted underneath the supporting frame, and an electric motor operatively connected to the wheel assembly such that the electric vehicle can be propelled by means of mechanical power. However, such conventional electric vehicle has several drawbacks.
Since the electric vehicle is powered by the motor, the wheel will be locked up in a rotatably movable manner when the motor is out of battery. So, a rider may merely have a chance to carry the electric vehicle. Due to the heavy weight of the electric vehicle, it is an extremely difficult for the rider, even an adult, to carry the electric vehicle for a long distance.
An improved electric vehicle is developed that the wheels are capable of free rotating when the electric motor is used up its power. In other words, the electric vehicle must be employed with a clutch device for releasing the lock-up position of the wheels such that the wheels can be freely rotated when the wheels are disengaged with the motor. Therefore, when the motor is out of battery, the rider can push the electric vehicle instead of carrying the electric vehicle everywhere. However, it is unreasonable for a young child to push the electric vehicle for a long distance. Besides, the complicated mechanical structure of the electric vehicle will further increase the manufacturing cost thereof. So, an alternative is sought for.